Hemostatic devices and methods for use thereof

ABSTRACT

Materials and methods for reducing or preventing bleeding and associated side effects during and after percutaneous medical procedures.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. application Ser.No. 13/712,486 (filed Dec. 12, 2012) which is a Continuation-In-Partapplication of co-pending U.S. application Ser. No. 12,464,583 (filedMay 12, 2009), which claims priority to Provisional Patent ApplicationNo. 61/052,537 (filed May 12, 2008), which applications are entirelyincorporated herein by reference and made a part hereof.

TECHNICAL FIELD

This document relates to devices and methods for hemostasis duringpercutaneous medical procedures.

BACKGROUND

Percutaneous renal procedures can be used for a variety of medicalpurposes, including removal of kidney stones that are too large or toocomplex to be removed by another method, to remove or treat urothelialcancer in the urinary collecting system, or to treat kidney obstruction.These percutaneous surgical techniques generally utilize radiographicimagining to determine the precise location for desired access to akidney. Using a needle, a puncture is made through the back andunderlying tissues into the kidney. Once the tract has been established,a “safety” wire typically is passed from outside the body, through thekidney, and down the ureter toward the bladder. The tract is thendilated with a balloon or a rigid dilator, and a percutaneous sheath isplaced over the dilating device. The sheath provides a portal throughwhich different instruments and scopes can be placed in order tocomplete the percutaneous renal procedure.

SUMMARY

As many as a third of patients who undergo a percutaneous renalprocedure will require a blood transfusion due to bleeding from thepuncture of the kidney. Such bleeding can cause severe complications,including loss of renal function, pain, prolonged hospitalization, needfor selective arterial embolization, or even the need for surgicalremoval of the kidney. This document provides hemostatic devices andmethods for their use, which can reduce or prevent bleeding inpercutaneous renal procedures and thus can reduce the risk of subsequentside effects. The devices provided herein can be readily deployed withminimal risk to the patient, and can be used for any suitablepercutaneous procedure, including treatment of kidney stones, kidneybiopsy, management of upper urinary tract cancers, or drainage of thekidney through a subject's back.

In one aspect, this document features an article comprising an elongatemember having an exterior surface, a hemostatic material in contact withat least a portion of the exterior surface, and a covering thatsurrounds the hemostatic material and is adapted to move slidably overthe elongate member. The elongate member can comprise a first end and asecond end. The hemostatic material can be in contact with a portion ofthe external surface adjacent to the first end, and can extend over thehemostatic material from the first end toward the second end. Thecovering can extend to the second end, and can comprise a protrusionadjacent to the second end. The elongate member can have an interiorlumen extending from the first end to the second end. The article canhave a diameter of 20 to 26 French and a length from about 3 cm to about20 cm. The elongate member can comprise a first portion having a firstdiameter and a second portion having a second diameter. The firstdiameter can be less than the second diameter, and the hemostaticmaterial can be coated on the first portion.

In another aspect, this document features a kit comprising an articleand a driver as described herein. In another aspect, this documentfeatures a method for reducing bleeding in a subject during or after amedical procedure that includes utilizing a percutaneous sheath to gainaccess to an internal organ, the method comprising inserting an articleas described herein into the subject through the percutaneous sheath,and actuating the article such that the tissue of the subject iscontacted by the hemostatic material. The internal organ can be akidney.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention pertains. Although methods and materialssimilar or equivalent to those described herein can be used to practicethe invention, suitable methods and materials are described below. Allpublications, patent applications, patents, and other referencesmentioned herein are incorporated by reference in their entirety. Incase of conflict, the present specification, including definitions, willcontrol. In addition, the materials, methods, and examples areillustrative only and not intended to be limiting.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a depiction of a typical percutaneous renal procedure.

FIG. 2A-2G is a depiction of exemplary embodiments of a hemostaticdevice.

FIG. 3 is a side view of an embodiment of a hemostatic device.

FIG. 4 is a side view of an embodiment of a hemostatic device in use.

FIG. 5 is a side view of an embodiment of a hemostatic device in use.

Like reference symbols in the various drawings indicate like elements.

DETAILED DESCRIPTION

This document provides hemostatic devices and methods for their use inpercutaneous procedures (e.g., percutaneous renal procedures). A typicalpercutaneous renal procedure is depicted in FIG. 1. A puncture is madethrough skin 10 of a subject's back, through the underlying tissues, andinto kidney 20. Once a tract has been established, one or more wires(e.g., wire 30) can be passed through the tract, through the kidney, anddown ureter 40 toward the bladder. When two wires are present, forexample, a dilating device can be placed over one of the wires (the“working wire”), while the other wire (the “safety wire”) can be alongthe outside of the dilating device. The tract then can be dilated, andpercutaneous sheath 50 can be placed over the dilating device. Eitherthe working wire or the safety wire can serve as a guide in case sheath50 becomes displaced during a subsequent procedure. The size of sheath50 can vary depending on the specific procedure, but often is 30 French(10.0 mm) in diameter. Sheath 50 can be hollow, providing a portalthrough which different instruments and scopes can be placed into thepatient. Upon completion of a procedure, sheath 50 can be withdrawn fromthe subject, whereupon bleeding may occur from the kidney as well as thesoft tissue and muscle of the back along the insertion/removal tract.The hemostatic devices described herein can be used to reduce or preventsuch bleeding, as well as the associated side effects.

FIGS. 2 and 3 provide depictions of exemplary hemostatic devicesaccording to some embodiments provided herein. Device 100 can comprisecylinder 105 having proximal portion 110, proximal end 115, distalportion 120, distal end 125, and exterior surface 130. In someembodiments, cylinder 105 can be hollow such that it has an interiorlumen extending through its length. This can allow for passage of, forexample, wires, nephrostomy tubes, scopes, or any other suitablearticles through device 100.

Device 100 can have any suitable size, and can be configured to moveslidably within a percutaneous sheath. The most commonly usedpercutaneous sheaths have diameters of 24, 28, and 30 French (8.0, 9.3,and 10.0 mm, respectively). The devices provided herein can be 4 to 8French less in diameter than the percutaneous sheath (e.g., 16, 18, 20,22, 24, or 26 French). Further, device 100 can have any suitable length.For example, cylinder 105 can have a length from about 8 cm to about 22cm (e.g., about 8 cm, about 9 cm, about 10 cm, about 11 cm, about 12 cm,about 13 cm, about 14 cm, about 15 cm, about 16 cm, about 17 cm, about18 cm, about 19 cm, about 20 cm, about 21 cm; or about 22 cm). Inaddition, the devices can be made from any suitable material, including,for example, plastic.

Device 100 can have hemostatic material 140 coated on all or a portionof exterior surface 130 of cylinder 105. Hemostatic material 140 canaccelerate a subject's natural ability to form blood clots. Any suitablehemostatic material can be used, including, without limitation,anti-fibrinolytics, fibrin sealants, matrix hemostats, and topicalhemostatic agents. Particular examples of hemostatic materials include,without limitation, gelatins such as SURGIFOAM™ (Johnson & Johnson;Piscataway, N.J.) and GELFOAM® (Pharmacia & Upjohn Co.; New York, N.Y.);collagen materials such as AVITENE® and ULTRAFOAM™ (CR. Bard, Inc.;Murray Hill, N.J.); oxidized regenerated cellulose materials such asSURGICEL® Fibrillar and NU-KNIT (Johnson & Johnson); thrombin (e.g.,pooled human or bovine thrombin); fibrin sealants such as TISSEEL®(Baxter Healthcare Corp.; Westlake Village, Calif.), EVICEL™ (Johnson &Johnson), VITAGEL™ (Orthovita, Inc.; Malvern, Pa.), and HEMASEEL®(Haemacure Corp.; Montreal, Quebec); polyethylene glycol polymers suchas COSEAL® (Baxter Healthcare) and DURASEAL® (Confluent Surgical;Waltham, Mass.); albumin and glutaraldehyde compositions such as B 1OGLUE® (Cryolife Inc.; Kennesaw, Ga.) and FOCALSEAL® (Focal, Inc.;Lexington, Mass.); glutaraldehyde resorcinol formalin and collagen (GRF;C.R. Bard, Inc.); gelatin and thrombin compositions such as FLOSEAL®(Baxter Healthcare Corp.) and SURGIFLO® (Johnson 8,z Johnson); granularzeolite powders such as QUIKCLOT® (Z-Medica Corp.; Wallingford, Conn.);chitin compositions such as HEMCON® (HemCon Medical Technologies, Inc.;Portland, Oreg.); and microporous polysaccharide hemospheres such asMPH® (Medafor Inc., Minneapolis, Minn.). Hemostatic material 140 can bedissolvable in urine and can be quickly reabsorbed to prevent clots orplugs in the urinary tract, fistulas (abnormal connections between theurinary collecting system and the retroperitoneum or back), or otherproblems. The entirety of exterior surface 130 can be coated withhemostatic material 140, or just a portion (e.g., distal portion 120)can be coated with hemostatic material 140. As shown in FIG. 2, forexample, the diameter of cylinder 105 can vary along its length, suchthat it can have a smaller diameter in some areas than in others.Regions of smaller diameter can serve as reservoirs or channels for ahemostatic material. The diameter of distal portion 120 can be reducedas compared to the diameter of proximal portion 110, and hemostaticmaterial 140 can be placed over distal portion 120. In some cases, forexample, outer surface 130 of cylinder 105 can define one or morechannels (e.g., channels extending from distal end 125 along distalportion 120 toward proximal end 115 that are perpendicular to thelongitudinal axis of cylinder 105, or that are at an angle with respectto the longitudinal axis of cylinder 105, or channels that extendlaterally around the circumference of outer surface 130 within distalportion 120). Such embodiments, shown in FIG. 2 for example, haveportions of relatively reduced diameter that allow device 100 to hold agreater amount of hemostatic agent 140 where it will be needed most,i.e., near distal end 125, which can be placed in contact with kidneytissue. The cross-sectional shape of the channels or areas of reduceddiameter may vary. As shown in FIGS. 2B-2D, for example, the channels orareas of reduced diameter could be V-shaped, rectangular, orsemicircular in cross-section, The diameter of cylinder 105 can alsoprovide circumferential pressure along the percutaneous tract whilehemostatic material 140 takes effect. The cylinder 105 may also beinflatable, as shown FIG. 2F and FIG. 2G. The hemostatic material mayextend around the circumference of the outer surface of the inflatablecylinder 105, as shown in FIG. 2F, thereby placing the hemostaticmaterial in circumferential contact with kidney tissue as the cylinder105 becomes inflated, as shown in FIG. 2G. The outer surface of thecylinder 105 can provide pressure along the percutaneous tract of thekidney while the hemostatic material takes effect.

Device 100 also can include barrier 150 over hemostatic material 140.Barrier 150 can be, for example, a thin plastic film, and can be brokenand/or removed at the time the percutaneous sheath is removed to allowfor precise deployment of hemostatic material 140 along the course ofthe percutaneous tract. In some embodiments, barrier 150 can be a heatsealed plastic covering that can break away at distal end 125. In somecases, barrier 150 can be scored or perforated at or near distal end 125to facilitate breakage and removal of barrier 150. The presence ofbarrier 150 over hemostatic material 140 can prevent early activation ordislodgement of material 140, as most percutaneous tubes are subjectedto a constant flow of blood, irrigant (normal saline), or urine duringuse. Further, exterior surface 130 of cylinder 105, which interfaceswith hemostatic material 140, can be negatively charged, sufficientlyslick, or coated in such a way that hemostatic material 140 willpreferably maintain contact with bodily tissue rather than with device140 once barrier 150 is broken and/or removed. For example, exteriorsurface 130 can be coated with TEFLON®. This can facilitate removal ofdevice 100 after a suitable length of time (e.g about 30 seconds toabout 5 minutes), without dislodging a newly formed clot.

Device 100 also can have a protrusion (e.g., handle or collar 160) thatis connected to barrier 150 and that can be actuated to break or removebarrier 150 from device 100 in order to expose hemostatic material 140.Collar 160 can be located at or near proximal end 115 of cylinder 105.By pulling on collar 160 in a proximal direction, a user can breakbarrier 150 (e.g., at distal end 125) and then pull barrier 150proximally over the surface of cylinder 105, exposing hemostatic agent140 to the surrounding tissue.

Device 100 also can have include one or more radio-opaque markers (e.g.,radio-opaque marker 170) so that the position of device 100 can beobserved radiographically during deployment. Cylinder 105 of device 100also can allow for visual confirmation of deployment at the edge of therenal tissue. Marker 170 can be positioned anywhere on device 100, e.g.,at or around distal end 125 of cylinder 105 as shown in FIG. 3, or alongthe surface of distal portion 120. Suitable radio-opaque materials areknown in the art, as are methods for depositing radio-opaque markers onmedical devices.

FIGS. 4 and 5 depict embodiments of methods for using device 100. Once amedical procedure (e.g., a kidney stone removal or a kidney biopsy) iscomplete and other medical devices are removed from percutaneous sheath50, device 100 can be inserted into sheath 50 until distal end 125reaches kidney 20 (e.g., the distal end of sheath 50 within kidney 20).A user then can insert a driver (e.g., cylindrical driver 180 havingdistal end 185) into percutaneous sheath 50 (as indicated by the arrowin FIG. 4), advancing driver 180 until distal end 185 contacts proximalend 115 of cylinder 105. In some embodiments, cylinder 105 can have ashelf or protrusion at or adjacent to proximal end 115, on which driver180 can seat and be used to exert force on cylinder 105 in a distaldirection. The user then can remove percutaneous sheath 50 from thesubject by pulling it over driver 180. Simultaneously or subsequently,the user can move handle 160 in a proximal direction, pulling barrier150 over exterior surface 130 of cylinder 105 and removing barrier 150from the subject's body while holding cylinder 105 in place. This can beaccomplished, for example, by exerting force in a distal direction ondriver 180 (arrow “a” in FIG. 5) while exerting force in a proximaldirection on handle 160 (arrow “b” in FIG. 5). In some embodiments, theaction of removing sheath 50 can also move handle 160 in a proximaldirection. In either embodiment, such movement can expose hemostaticmaterial 140 to the subjects kidney and any other tissue surroundingdevice 100 within the subject's body. It is noted that driver 180 can behollow such that a lumen extends through its length. Such a hollowdriver, in combination with a hollow hemostatic device can allow a userto insert or maintain wires or other instruments into the subject'skidney as needed.

Other Embodiments

It is to be understood that while the invention has been described inconjunction with the detailed description thereof, the foregoingdescription is intended to illustrate and not limit the scope of theinvention, which is defined by the scope of the appended claims. Otheraspects, advantages, and modifications are within the scope of thefollowing claims.

What is claimed is:
 1. A method of achieving hemostasis in apercutaneous tract of a kidney while surgery on said kidney isperformed, said method comprising: inserting a hemostatic device intosaid percutaneous tract, said hemostatic device having an elongatemember of integral one-piece construction comprising an exteriorsurface, an interior surface, a distal end, and a proximal end, and acovering, said exterior surface and said interior surface extending fromsaid distal end to said proximal end, said elongate member having afirst tubular portion integrally connected to a second tubular portion,said first tubular portion and said second tubular portion each havingan external diameter and a length, wherein said length of said firsttubular portion extends from said distal end to said second tubularportion and said length of said second tubular portion extends from saidproximal end to said first tubular portion, wherein said externaldiameter of said first tubular portion is less than said externaldiameter of said upper tubular portion; removing said covering of saidhemostatic device; contacting bodily tissue of said percutaneous tractwith hemostatic material disposed around said first tubular portion andextending along said length of said first tubular portion, said layer ofhemostatic material having a depth substantially equal to D₁-D₂ where D₁is said external diameter of the second tubular portion and D₂ is saidexternal diameter of said first tubular portion; inserting a surgicalimplements into and through said interior surface after said hemostaticdevice is inserted in said percutaneous tract, said surgical instrumentbeing unattached to said elongate member; achieving said hemostasis ofsaid bodily tissue while said surgical implements remains in saidinterior lumen for performing surgery on said kidney; removing saidsurgical instrument before removing said hemostatic device from saidkidney; and removing said hemostatic device from said kidney after saidhemostatis achieved and said surgery is complete.
 2. The method as setforth in claim 1 wherein said first tubular portion that contains saidhemostatic material includes a synthetic resin to facilitate contactbetween said hemostatic material and said bodily tissue after saidcovering is removed.
 3. The method as set forth in claim 1 wherein saidfirst tubular portion that contains said hemostatic material isnegatively charged to facilitate contact between said hemostaticmaterial and said bodily tissue after said covering is removed.
 4. Themethod as set forth in claim 1 further comprising the step of confirmingthe proper placement of said hemostatic device in said percutaneoustract by detecting a radio-opaque marker on said elongate member.
 5. Themethod as set forth in claim 1 further comprising the step of inflatingat least a portion of said hemostatic device to apply pressure to saidbodily tissue.
 6. The method as set forth in claim 1 wherein saidexterior surface contains at least one channel portion extending alongsaid exterior surface in a direction from said distal end to saidproximal end for retaining said hemostatic material.